Aside from being FOSS I would say not really other than Rawtherapee is more of a Lightroom-type program in that it allows the settings to be applied to multiple RAW files.

RawTherapee is also known to be a more "true" conversion tool than Lightroom.

With Lightroom there is an extra layer of intelligence/magic between what the sliders say they do, and what they actually do. In most cases this works well and makes the life easier for the user, but in some cases it can drive people nuts.

An example of this is "ISO-less" photography:

With modern cameras, the need for using in-camera ISO is disappearing. Except for the lowest ISO values, increasing the ISO in the camera gives the same image quality loss as using a lower ISO and then increasing light in post processing. Both are just different ways of amplifying the light - except that the latter method preserves more highlight information so you can end up with a better result after post processing. So some people prefer to use this method. (And it can also be regarded a workaround for the missing Auto ISO in Manual on most Sony cameras.)

When you do ISO-less photography, you need a raw converter which can amplify the light in the photo in the same way as if you had increased the ISO in the camera. That is really what the Exposure slider in a raw converter is supposed to do. And in Rawtherapee it does just that. But in Lightroom some other magic is added, and you end up with a photo with a ridiculous amount of contrast and have to compensate on the other sliders.

I prefer Lightroom, though. All that magic helps me to achieve a good result faster, even though it also prevents me from doing some things.